Core drill



July 26, 1927,

L. F. BONNEY CORE DRILL Filed Dec. 11. 1926 \w\ v \\\V\\\\\ PatentedJuly 26, 1927.

UNITED STATES PATENT OFFICE.

LY'N'N I. BONNEY, OF LOS ANGELES, CALIFORNTA, ASSIGNOR T OIL'WELL COREDRILL- ING COMPANY, OF LOS ANGELES, CALIFORNIA, A CORPORATION OFCALIFORNIA.

CORE DRILL.

Application filed December 11, 1926. Serial No. 154,080.

This invention relates'to a core drill, and refers particularl to thetype of core drill which is employe in taking cores during the drillingof wells, such as oil wells.

In the drilling or taking of cores from core drills, the cutters orcutting parts of the drill are subjected to rapid wear. Thisnecessitates a repeated replacement of the cutting parts of the coredrill.

An object of the present invention is to provide a core drill with anovel form of detachable cutter.

Various further objects and advantages of the present invention will beunderstood from a description of the preferred form or example of a coredrill embodying the invention. For this purpose, reference is made tothe accompanying drawings, in which:

Figure 1 is an elevation mainly in vertical section,

Figure 2 is a section on the line 22 of Figure 1,

Figure 3 is an elevation. of the detachable cutter for the core drill,and,

Figure 4 is a fragmental elevation of the lower end of the core drillwith the cutter removed.

Referring to the drawings, 2 indicates the lower end of a string of pipeemployed for supporting and rotating the core drill in the Well holes 3indicates a core receiving barrel for the core drill which barrel, it isunderstood, may as usual be of any desired length and normally isprovided at its upper end with a' check valve (not shown). The corereceiving barrel is threaded near its lower end, as indicated at 4, to ahead" 5. The head 5 in turn has its upper end threaded as indicated at 6to a tool joint 7 which, in turn, is threaded as indicated at 8 to thelower end of the stand of drill pipe 2. The core barrel 3 is ofsmaller'outer diameter than the inner diameter ofthe tool joint 7, thusprovidi an annular space'9 therebetween by Whlifil flushing fluid may bepassed from the stand of drill pipe to the core drill head 5. The coredrill head '5 is cut away, as indicated at 10, to provide a downwardlyfacin annular shoulder, and below said shoul er.10, the head tapers orcurves inwardly, as indicated at 11. The head 5 is also provided with aplurailty of downwardly extending and circumferentially spaced apartlugs 12 which thus form radial extenslons ofthflower end of the head.Said core drills The head 5 is also provided with a plurality ofradially extending openings 15 tapering. to contract outwardly, saidopenings 15 being formed in the head 5 in the rear'part of the lugs 12.

16 indicates a detachable cutter forthe core drill which has a slidingfit with the lower end of the head 5, the upper end of the cutter 16engaging the shoulder 10. The major portion of the cutter 16 is taperedor curved downwardly and inwardly, as indicated at 17, fitting the outersurface of the tapered or curved end 11 of the head 5. Through thecutter 16, there are provided vertical openings 18 fitting the lugs 12of the head 5, the cutter 16 thus being provided with a plurality oftorque receiving bearing faces 19 engaging the bearing faces 14 of thehead. The cooperating torque receiving bearingl faces 14 and 19 resistthe torque load upon t e cutter 16 and head 5 during drill-' ingoperations, and thus prevent said load from being applied to the meansfor locking or holding the cutter 16 upon the head 5.

The cutter 16 may be provided with any desired form or shape of cuttersadapted for, cutting cores in well drilling, being indicated as havingthecore cutting teeth 20 together with the lower set of reaming cutters21 contiguous with the lower end of the core cutting teeth 20. There isalso preferably pro vided a plurality of enlarged reaming cutters 22,the lower ends of which terminate above the core cutting teeth 20 sothat said core cutting teeth have a lead or are advanced infront of thelarge reaming cutters 22. All of said cutters may be an inte ral part ofthe head 16,

although it is un erstood, in practice, that they may be detachablysecured thereto and even when integral therewith maybe of a different orharder composition than the rest of the cutter head, being attached tothe rest of the cutter head by being welded thereon.

The cutter 16 is also preferably provided with an openin 23 adjacenteach lug 12 of the head 5 for supplied to the core ischarging theflushing fluid rill in proximity to fluid is discharged from ports 23immediate- 'lyadjacent the cutting edges of at least a part of thecutters 22, thereby being deposited in a position for most effectivecooling of the cutters and for most effectively washing and clearingaway the detritus formed thereby.

The cutter 16 is provided with tapering openings 24 aligning with theopenings 15 in the lugs 12 of the head 5 and said openings receivetapered pins 25 which serve to support and lock the cutter 16 on thehead 5. The inner ends of said pins 25 are in turn engaged by the corebarrel 3 whereby they are locked in position.

The core drill also includes a core catcher 26 of any suitable designsuch, for example, 'as formed by spring fingers 27. While said springfingers 27 are indicated as formed on a separate annular ring 28 belowthe core barrel '3, it is understood that said ring might constitute anintegral part of either the barrel 3 or the head 5 or cutter 16.

By the construction of core drill here in described, all of the cuttingparts of the drill are formed detachable from the remainder of the drillwith the result that they may be readily removed and others substitutedtherefor when worn. Moreover, the detachable cutter 16 is positivelysecured or locked to the core drill by means preventing any of thetorque or load applied to the drill being imposed upon the lockingmeans. Thereby, there is provided a core drill assembly by which thedetachable cutters may be very readily and easily engaged and disengaged. Moreover, the construction of core drill thus describedprovides a means for discharging the flushing fluid from the cutters atthe most desirable point.

While the core drill herein described is well adapted for carrying outthe objects of the present invention, various modifications and changesmaybe made without departing from the invention and the inventionincludesall such modifications and changes as come within the scope ofthe appended claims.

I claim:

1. A core drill comprising a head, a core receiver secured to the head,a cutter loosely fitted to the head, and pins locking the cutter uponthe head, said pins being locked in place by engagement with the corereceiver.

2. A core drill comprising a head, a core receiver secured to the head,the head having a plurality of circumferentially spaced apart lugs,flushing passages extending through said lugs, a cutter having a loosefit with said head, there being cooperating torque receiving bearingfaces between said cutter and said lugs, and openings in said cuttercommunicating with the flushing passages within said lugs.

3. A core drill comprising a head, a core receiver secured to the'head,means for securing a drill pipe to the head, said head being providedwith a plurality of circumferentially spaced apart outer lugs, a cutterhaving a loose fit with said head, the head and'cutter havingcooperating torque thrust receiving faces, means for passing flushingfluid through the head and cutter, registering openings in said head andcutter tapering to contract outwardly, pins fitting said openings, and amember secured to said head engaging the inner ends of said pins forlocking the same in place.

4. core drill comprising a head, means for securing the head to a drillpipe, a core receiver secured to the head, lugs on the head a cutterhaving a loose fit with said head and engaging radial shoulders on saidlugs the cutter being provided with both core drilling and reamingteeth, and means for detachably locking the cutter to the head.

Signedat Los Angeles, California, this 3 day of December 1926.

LYNN F. BONNEY.

